package nowcoder;

import java.util.Arrays;
import java.util.Scanner;

/**
 *  【牛客题号: KY168字符串内排序】
 *  https://www.nowcoder.com/practice/cc2291ab56ee4e919efef2f4d2473bac?tpId=40&rp=1&ru=%2Fta%2Fclassic-code&qru=%2Fta%2Fclassic-code%2Fquestion-ranking&difficulty=&judgeStatus=&tags=&title=168&gioEnter=menu
 */
public class InStringSort {
    public static void main(String[] args) {
        Scanner s = new Scanner(System.in);
        while(s.hasNext()){//多组输入牛客要用很重要
            String string = s.next();
            String[] stringArray = string.split("");
            int[] stringBecomeNum = new int[stringArray.length];
            for (int i = 0 ; i < stringBecomeNum.length ; i++){
                stringBecomeNum[i] = Integer.valueOf(stringArray[i].charAt(0));
            }
            Arrays.sort(stringBecomeNum);

            for(int i = 0 ; i < stringBecomeNum.length ; i++){
                System.out.print((char)stringBecomeNum[i]);
            }

        }

    }
}
